<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2012 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
// $Id: CacheApc.class.php 2728 2012-02-12 04:12:51Z liu21st $


/**
 +-------------------------------
 * Apc缓存驱动类
 +-------------------------------
 */
class CacheApc extends Cache {
	
	/**
     +----------------------------------------------------------
	 * 架构函数
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 */
	public function __construct($options = '') {
		if (! function_exists ( 'apc_cache_info' )) {
			throw_exception ( L ( '_NOT_SUPPERT_' ) . ':Apc' );
		}
		if (! empty ( $options )) {
			$this->options = $options;
		}
		$this->options ['expire'] = isset ( $options ['expire'] ) ? $options ['expire'] : C ( 'DATA_CACHE_TIME' );
		$this->options ['length'] = isset ( $options ['length'] ) ? $options ['length'] : 0;
	}
	
	/**
     +----------------------------------------------------------
	 * 读取缓存
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param string $name 缓存变量名
     +----------------------------------------------------------
	 * @return mixed
     +----------------------------------------------------------
	 */
	public function get($name) {
		N ( 'cache_read', 1 );
		return apc_fetch ( $name );
	}
	
	/**
     +----------------------------------------------------------
	 * 写入缓存
	 *
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param string $name 缓存变量名
	 * @param mixed $value  存储数据
	 * @param integer $expire  有效时间（秒）
     +----------------------------------------------------------
	 * @return boolen
     +----------------------------------------------------------
	 */
	public function set($name, $value, $expire = null) {
		N ( 'cache_write', 1 );
		if (is_null ( $expire )) {
			$expire = $this->options ['expire'];
		}
		if ($result = apc_store ( $name, $value, $expire )) {
			if ($this->options ['length'] > 0) {
				// 记录缓存队列
				$this->queue ( $name );
			}
		}
		return $result;
	}
	
	/**
     +----------------------------------------------------------
	 * 删除缓存
	 *
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @param string $name 缓存变量名
     +----------------------------------------------------------
	 * @return boolen
     +----------------------------------------------------------
	 */
	public function rm($name) {
		return apc_delete ( $name );
	}
	
	/**
     +----------------------------------------------------------
	 * 清除缓存
     +----------------------------------------------------------
	 * @access public
     +----------------------------------------------------------
	 * @return boolen
     +----------------------------------------------------------
	 */
	public function clear() {
		return apc_clear_cache ();
	}

}